Regarding the issue of cable voltage drop
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Check the voltage drop based on cable length. I don’t know how to calculate the voltage drop~ I only know that it is related to the length of the wire, its cross-sectional area, and the material of the wire conductor~ but I have no idea how to do the calculation~ I ask experts for help. There’s also a small question: the minimum short-circuit current at the end of the circuit should be sufficient to ensure that the protective devices operate reliably~ How exactly is this achieved? Examples would be helpful:$
To check the voltage drop based on cable length, A Lai has uploaded a calculation formula for reference: ΔU = √3 *IB* (R cos ϕ + X sin ϕ ) *L, where IB is the full-load current in amps； L: Cable length, km ； R: Resistance of the circuit conductor, Ω/km. Note: When the cross-sectional area S exceeds 500 mm2, R can be ignored.
What is the value of that X before sin? For example, for a 100-meter copper wire with 95 MM thickness
How are the two values of cos ϕ + X sin ϕ determined?
In studying*, I really don’t understand this
For motor cable voltage drop, it is necessary to calculate the operating voltage drop and the starting voltage drop. cosφ has two values: the power factor when the motor is operating and the power factor during startup. Similarly, I also has two values: one is the current during operation, and the other is the starting current. The pressure drop needs to be calculated separately